Stainless steel welded tube black cause and treatment method

In fact, in accordance with the normal speaking, good stainless steel welded tube processing products will not appear in this situation, if stainless steel welded tube products in the long-term use of black and dark. This is because the air under the action of stainless steel welded tube produced a layer of oxide film, the main role of this layer of oxide film is to maintain the stainless steel inside the metal do not continue to be oxidized, this layer of oxide film do not have to erase deliberately, and no damage to the pipe. Different materials of stainless steel welded tube because there are some differences in the element content, so the oxidation of the film color will be different, but it has no effect on the pipe. In this case, there is no need for other processing. If you feel it is not beautiful to use, you can go to the stainless steel welded tube processing center to do polishing treatment, which can be easily solved.
If it is stainless steel welded tube after welding, stainless steel welded tube inside and outside the surface black, yellow, this is because the purity of the welding gas is not enough or the back because of high temperature oxidation and other reasons, the use of the following three methods can avoid such things.
1. The purity of argon used in welding stainless steel welded tube is improved to pure argon. From the outside surface of stainless steel welded tube alone, pure argon is obviously brighter than the brightness of argon welded out.
2. Back argon to do a good job of protection, the important stainless steel welded tube after welding to do the back protection, otherwise, high temperature oxidation will lead to the back through the welding layer oxidation defects, grinding the back welding with slag, so the protection can effectively prevent the back oxidation.
3. You can apply the backside protective agent on the back side, which is a kind of argon protection can be saved. It can be applied with a thickness of about 1mm, and then form a thin film on the back side to form a protective layer during the front welding.
If it has been found that stainless steel welded tube welding black can be cleaned by pickling passivation paste, is to use acid to corrode the surface of the black oxide layer, and then rinse clean with water, you can.

Post time: Mar-13-2023